[Shaffer]

As a FYI for anyone interested in getting into tube rolling, I just listed my LDIII for sale with many upgraded tubes:

http://www.head-fi.org/t/772250/fs-little-dot-mkiii-with-many-upgraded-tubes-some-of-the-best-available#post_11707625

 

[gibosi]

  Well i have to get a $10 headphone now. I don't have any. What is the reason for Woo and Little Dot recommending headphones to be plugged in during startup? Is there anything to do with the vaccuum tubes or something?

 
The Woo has an output transformer which can be damaged if the amp is run without a load. And it appears that Woo has incorporated a special circuit to protect the headphones when the amp is turned on and while it warms up. As for the LD, I have no idea why the company recommends that cans be plugged in before turning the amp on. Neither an OTL amp (LD II, III and IV) nor a hybrid (LD 1+) can be damaged if turned on without the cans plugged in. Following the advice of MisterX guarantees that your ears and/or headphones will not be damaged if the amp fails catastrophically. So to my way of thinking, protecting ears and expensive cans is the best practice, especially since it doesn't hurt the amp. And this is my standard operating procedure as well.

 

[mordy]

Hi rovopio,
 
The Ei 6HM5 tubes have a flash heating feature (no doubt for military purposes) to heat up the filament quickly and get the tube up to operating temperature quickly. The start up flash is perfectly normal for this tube.
 
However, when it happened to me the first time I was using the tube I got scared and thought something went wrong with my amp, but this is nothing to worry about  with this specific tube. Somewhere on this blog I managed to post a picture of it as well.
 
As is generally agreed, the 6HM5 tubes are among the best plug and play driver tubes for the Little Dot MKIII. To get better performance, you need to upgrade to dual triodes with the required external voltage supply, voltage regulator and special adapters.
 
Another simpler step is to stay with the 6HM5 tubes and upgrade to plug and play power tubes (will require socket adapters) such as 6SN7.
 
Good luck!

 

[Shaffer]

[...]

Another simpler step is to stay with the 6HM5 tubes and upgrade to plug and play power tubes (will require socket adapters) such as 6SN7.

Good luck!

That's the setup I used a lot. The Yugos compliment a lot of 6SN7s.

 

[mimart7]

 
These just arrived, and I have 2 cooking, now.  WW 2 vintage.

 

[mordy]

Hi m7,
 
I have these tubes in a different box - not sure if u r going to like them. IMH experience the 6AK5 Tung Sol tubes from the 50s and 60s sounded better. Amazing that these tubes that are 70 years old still work well......

 

[rovopio]

 

 
I just paid for the OPA2107AP from Janeh2100. She replied very quickly to my questions. Mainly to ask about Express Shipping.
ps: it's extra $4. Which is completely fine as I don't have to wait 3 weeks for it...
 
Got the 6hm5 as well from Tachonz.

 

[mimart7]

  Hi m7,
 
I have these tubes in a different box - not sure if u r going to like them. IMH experience the 6AK5 Tung Sol tubes from the 50s and 60s sounded better. Amazing that these tubes that are 70 years old still work well......

They are still cooking, but i will look into Tung-Sols with a later manufacturing date.

 

[rovopio]

So... my LD i+ arrived. Inside the Interconnect Cable Package I found the cable, a 6.3mm adapter, and 2 rectangular thing.
1) What does that called and what is the purpose of that rectangular thing?
 

   

 
2) By the way, May I ask what is the Factory Default Setting of the LD i+? Is it already at Low Gain with 6J1 tube setting?
 
3) Also one more question, I don't get a paper invoice from David. Is that normal?
The manuals for LD i+ stated that warranty claims need to be accompanied by proof of purchase. I only have PP screenshot as of now.
 
I did ask him for Digital Invoice scan a week ago while waiting for shipping and while he answered my other questions in that same e-mail, he didn't reply to my request on asking for Digital Invoice. I figured at the time, maybe he didn't do Digital Invoice request, and I can always scan the paper by myself when the LD i+ arrived but... apparently I didn't get a paper invoice either.
 
Is this normal or he just happened to forgot?
 
Edited :: 4) David shipped me the US Power Cord also. The country I live in uses the UK-type plug.
My question basically is... Can I use the supplied US Power Cord and plug it to Passive Traveller's All-in-One converter? Will that be safe?
 
Or do I have to get a new 220V UK-plug Power Cord instead?
 
If there is any people here living in the Europe I'd appreciate the answer to this specific question. Cheers...

 

[mimart7]

  So... my LD i+ arrived. Inside the Interconnect Cable Package I found the cable, a 6.3mm adapter, and 2 rectangular thing.
1) What does that called and what is the purpose of that rectangular thing?
 
 
2) By the way, May I ask what is the Factory Default Setting of the LD i+? Is it already at Low Gain with 6J1 tube setting?
 
3) Also one more question, I don't get a paper invoice from David. Is that normal?
The manuals for LD i+ stated that warranty claims need to be accompanied by proof of purchase. I only have PP screenshot as of now.
 
I did ask him for Digital Invoice scan a week ago while waiting for shipping and while he answered my other questions in that same e-mail, he didn't reply to my request on asking for Digital Invoice. I figured at the time, maybe he didn't do Digital Invoice request, and I can always scan the paper by myself when the LD i+ arrived but... apparently I didn't get a paper invoice either.
 
Is this normal or he just happened to forgot?
 
Edited :: 4) David shipped me the US Power Cord also. The country I live in uses the UK-type plug.
My question basically is... Can I use the supplied US Power Cord and plug it to Passive Traveller's All-in-One converter? Will that be safe?
 
Or do I have to get a new 220V UK-plug Power Cord instead?
 
If there is any people here living in the Europe I'd appreciate the answer to this specific question. Cheers...

You can use a converter, or you buy a new cord, from a local shop.  They should be inexpensive.

 

[rovopio]

  You can use a converter, or you buy a new cord, from a local shop.  They should be inexpensive.

 
Thanks mimart7. I bought a OPA2107 and 6hm5 as well, and are now waiting for them to arrived. I think my Stock Tube noticeably hisses. I read LD i+ manual and it said to clean them I have to use the deoxIT. Checked out the local price, they are selling them at $55. Wow, that's more expensive than a MUSES02 so I'll pass... lol
 
By the way, did you get a paper invoice when you bought your Little Dot amp? Or same like me, you don't get any invoice and only got that yellow chinese-written small paper (that seems like a warranty card) also?

 

[mimart7]

I believe I got the same card.  As far as the hissing goes, there really is zero need for that cleaning solution.  Try reseating the tubes, and they need to cook for at least 20 hours.  Your headphones need to be plugged in, and music does not have to be playing.  You can let them cook for up 8 hours at a time, with a minimum of 30 minutes of the amp being powered off.  Do you hear the hissing when you have the amp turned, with no music playing?

 

[rovopio]

  I believe I got the same card.  As far as the hissing goes, there really is zero need for that cleaning solution.  Try reseating the tubes, and they need to cook for at least 20 hours.  Your headphones need to be plugged in, and music does not have to be playing.  You can let them cook for up 8 hours at a time, with a minimum of 30 minutes of the amp being powered off.  Do you hear the hissing when you have the amp turned, with no music playing?

 
Yes, only when the music is not playing.
When the music is playing, it's so loud even at volume pot 10 (7 o'clock), I can't hear the hissing. It's quite loud for my Grado headphone.

 

[mimart7]

   
Yes, only when the music is not playing.
When the music is playing, it's so loud even at volume pot 10 (7 o'clock), I can't hear the hissing. It's quite loud for my Grado headphone.

Power down the amp, wait 10 minutes, swap the sockets the the tubes are in.

 

[rovopio]

  Power down the amp, wait 10 minutes, swap the sockets the the tubes are in.

 
By swapping the sockets, do you mean I should move Tube A from the left side to the right side and vice-versa?
Or do you mean I should open the amp's bottom chassis and swap the white sockets?
 
By the way, is there a specific way to handle the tubes? Like I shouldn't touch them by hand or something?
So far I use tissue to take them on and off to minimize fingerpirnts. But if there is a proper way of handling tubes... I will do it.